Hey there. This is kind of an idea I'm sharing for an alternate universe inspired somewhat on the 1960s Batman series.

Casting:

Bruce Wayne/Batman: Rarity/Batmare

Dick Grayson/Robin: Sweetie Belle/Roebin

Alfred: Fancy Pants

Aunt Harriet: Cookie Crumbles (mother instead of aunt; in this universe, only Rarity and Sweetie's father was killed, not both of their parents)

Barbara Gordon/Batgirl: Apple Bloom/Batfilly (Applejack's little sister instead of daughter)

The Joker: Pinkie Pie

The Riddler: Twilight Sparkle

Catwoman: Capper Dapperclaws

King Tut: Princess Luna/Nightmare Moon

Egghead: Cozy Glow

Commissioner Gordon: Applejack

Chief O'Hara: Rainbow Dash

Britt Reid/the Green Hornet (crossover): Trixie Lulamoon

Kato (crossover): Starlight Glimmer

Lenore Case (mentioned/crossover): Sunburst.

Frank Scallion (mentioned/crossover): Prince Blueblood

Wonder Woman (1970s/crossover/comics): Princess Cadance

And any other casting you can think of for this series (including for the other villains and the other heroes in the comics crossovers) go right ahead. As well as differences between this and the main 60's Batman series that would still keep in a campy, tongue-in-cheek adventure show while not being a total rehash.

7939537
Interesting idea.

7939681
Thanks very much, once again.